chapter 2 Flashcards
1
Q
mechanisms of heredity: autosomes
A
first 22 pairs of chrosomes (these are all matching pairs)
2
Q
mechanisms of heredity: sex chromosomes
A
these are the 23rd pair of chromosomes, these determine the sex of the child (xx is female, xy is male)
3
Q
mechanisms of heredity: deoxyribonucleic acid (DNA)
A
this is a molecular compound of four nucleotide bases that is the biochemical basis of heredity
- the four bases are: adenine, thymine, guanine, and cytosine
- thymine can only bond with adenine
- guanine can only bond with cytosine
4
Q
mechanisms of heredity: gene
A
group of nuceotide bases that provide a set of biochemical instructions
5
Q
mechanisms of heredity: genotype
A
person’s hereditary makeup
6
Q
mechanisms of heredity: phenotype
A
physical, behavioural, and psychological features that result from the interaction between one’s genes and the environment
7
Q
mechanisms of heredity: alleles
A
variations of genes
8
Q
mechanisms of heredity: homozygous
A
when the alleles in a pair of chromosomes are the same
9
Q
mechanisms of heredity: heterozygous
A
when the alleles in a pair of chromosomes are different (one can mask the other)
10
Q
mechanisms of heredity: dominant gene
A
form of an allele whose chemical instructions are followed
11
Q
mechanisms of heredity: recessive gene
A
allele whose instructions are ignored when it is combined with a dominant allele
-when this happens it is called dominant-recessive inheritance, or single-gene inheritance
12
Q
mechanisms of heredity: incomplete dominance
A
this is a situation where one allele does not dominate the other completely, this is the cause of traits like sickle-cell trait
13
Q
mechanisms of heredity: sickle cell trait
A
this is a dissorder where individuals show signs of mild anemia when they are deprived of oxygen (occurs in individuals who have one dominant allele for normal blood cells and one recessive sickle-cell allele)
14
Q
genetic dissorders
A
- these can be inherited: where a child inherits a gene for a dissorder from one or both parents
- or they can involve more or fewer chromosomes, as can happen when parents eggs or sperm do not form properly
15
Q
inherited disorders: phenylketonuria (PKU)
A
this is when the infant lacks a liver enzyme
- affects the ability to break down the phenylalanine, which if accumulated, can be a neurotoxic
- this is a recessive trait
16
Q
inherited disorders: huntingtons disease
A
a progressive and fatal type of dementia
-this is a dominant trait, which is rare of serious dissorders
17
Q
abnormal chromosomes: down syndrome (trisomy 21)
A
this is the most common chromosomal dissorder
- this person would have unusual charictaristics, impared cognitive development, and a shortened life expectancy
- they have an extra 21st chromosome, often provided by the egg
18
Q
abnormal chromosomes: problems with autosomes and sex chromosomes
A
- when there is a problem with the autosomes it is typically very damaging, and often result in spontaneous abortion
- if there is a problem with the sex chromosomes there are also problems, however they would be less severe (unless you are missing the x chromosome, which the baby would die before birth)
19
Q
abnormal chromosomes: problems with sex chromosomes: klinefelters syndrome
A
XXY would look like:
- tall
- male
- small balls
- sterile
- below-normal intelegence
- passive
XYY would loook like:
the same, but no small balls, not sterile, and not passive
20
Q
abnormal chromosomes: problems with sex chromosomes: turners syndrome
A
X
this is a female, short, limited development of secondary sex charictaristics, problems perceiving spatial relations
21
Q
abnormal chromosomes: problems with sex chromosomes: XXX syndrome
A
XXX
this is a female, normal stature, delayed motor and language development
22
Q
mechanisms of heredity: chromosomes
A
threadlike structures in the nuclei of cells that contain genetic material
-each sperm and egg contains 23 chromosomes, giving the new organism 23 pairs (46)
23
Q
heredity, envitonment and development
A
although certain aspects of heredity can greatly influence development, phenotypes are also under the influence of hte environment
24
Q
behaviour genetics:
A
this is the branch of genetics that studies the inheritence of behavioural and psycholoical traits
- most human traits vary as a matter of degree rather than catagory
25
behaviour genetics: polygenic inheritance
when phenotypes are the result of the combined activity of many seperate genes
-most of these traits fall into a normal distribution (so it is likely that you will get a mix as opposed to something on either end)
26
monozygotic twins
this is the result of when a single fertilized egg splits to form two new individuals (identical twins)
27
dizygotic twins
this is the result of the fertilization of 2 seperate eggs by two sperm (fraternal twins)
28
twins: the difference between the two kinds
monozygotic twins have 100% genetic overlap and dizygotic twins do not
29
how to study adopted children
adoption studies involve comparing adopted children to:
- parents, both biological and adoptive
- siblings, both biological and adoptive
30
paths from genes to behaviour: some general principles
1. heredity and environment interact dynamically throughout development
2. genes can influence the kind of environment to which a person is exposed
3. environmental influences tipically make children within a family different
31
from genes to behaviour: reaction range
this is when a genotype is manifested in reaction to the environment where development takes place so a single genotype can lead to a range of phenotypes
32
from genes to behaviour: niche-picking
this is when someone specifically picks out an environment that works with their genetic makeup
33
from genes to behaviour: non-shared environmental influences
these are the forces in a family that make siblings different from one another
34
from conception to birth: prenatal development, and the 3 stages
```
this is the many changes that happen to change a fertilized egg into a newborn human
-this takes about 38 weeks
three stages:
-period of the zygote (weeks 1-2)
-period of the embryo (weeks 3-8)
-period of the fetus (weeks 9-38)
```
35
from conception to birth: period of the zygote (and define zygote)
weeks 1-2
zygote: fertilized egg
- during the first week after fertilization, travels down the fallopian tube toward the uterus
- spends the second week in the process of implantation (this is where the zygote burrows into the uterine wall and establishes connections with a woman's blood vessels)
36
from conception to birth: period of the zygote: germ disc
this is the small cluster of cells near the centre of the zygote that will eventually develop into a baby
37
from conception to birth: period of the zygote: placenta
structure through which nutrients and wastes are exchanged between the mother and the developing child (this is formed from the layer of hte zygote's cells that is closest to the uterus)
38
from conception to birth: period of the embryo: embryo
term given to the zygote once it is completely embedded in the uterine wall
39
from conception to birth: period of the embryo: what happens
weeks 3-8
three layers form in this time:
-ectoderm: this is the outer layer of the embryo that will become the hair, skin, and the nervous system
-mesoderm: middle layer of the embryo, becomes the muscles, bones, and circulatory system
-endoderm: inner layer of the embryo, which will become the lungs and the digestive system
40
from conception to birth: period of the embryo: what the embryo is supported by
amnion: inner sac where the developign child rests
amniotic fluid: surrounds the embryo or fetus
umbilical cord: contains veins and arteries that connects the developing child to the placenta
41
from conception to birth: period of the embryo: cephalocaudal principle
sequence of growth that occurs from the head down (head to caudal/tail region)
42
from conception to birth: period of the embryo: proximodistal principle
sequence of growth that progresses from the inner to outer parts of the body
43
from conception to birth: period of the fetus: weight gain
weeks 9-38
- there is a great increase in size and weight durin this time
- at 3 weeks, less than 30g
- 4 months, about 120-240g
- from 4-9 months there is about 3.4kg more gained
44
from conception to birth: period of the fetus: the brain
all regions of the brain start to grow, especially the cerebral cortex (the wrinkled surface of the brain that regulates functions that are distinctly human)
45
from conception to birth: period of the fetus: month 3 developments
in a male: testes secrete a hormone that causes development of a penis and scrotum
female: dont have this hormone so they develop a vagina and labia
46
from conception to birth: period of the fetus: month 5-6 developments
this is when the hair starts to emerge
- lanugo: fine, silky hair that covers most of the skin surface of the fetus and is mostly shed prior to birth
- vernix: substance that protects the fetus's skin during development
47
from conception to birth: period of the fetus: age of variability
the age at which a fetus could survive (ususally 7 months after conception)
-however there are could be complications such as: trouble breathing due to immature lungs, and difficulty with regulatign temperature because the insuating layer of fat hasnt appeared
48
from conception to birth: period of the fetus: during the fetal period
- fetus becomes more active, and develops regular cycles of activity and inactivity (more active is a fussier baby)
- senses begin to function (they can sense the stuff in the uterine environment)
- stores some basic memories that are accesible after birth (moms voice and moms foods)
49
influences on prenatal development: general risk factors (3)
nutrition
stress
mothers age
50
influences on prenatal development: nutrition
- you should only gain about 25-35lbs
| - the mother should also reciecve adequete nutrition
51
influences on prenatal development: nutrition: spina bifida
a dissorder where he embryo's neural tube does not close properly
- this leads to problems with the spinal cord and nervous system
- can result from a diet lacking in folate
52
influences on prenatal development: nutrition: multivinamins
therea re ones for pregnant women that provide optimal levels of protiens, vitamins, and minerals that are essential for a childs healthy development
53
influences on prenatal development: foods that should be avoided
these foods should be avoided because they have a high risk of being contaminated with bacteria
- raw fish
- undercooked meat
- raw or lightly cooked eggs
- unpasturized milk or juices
- raw sprouts
54
influences on prenatal development: stress (define)
this is the physical and psychological responses to threatening or challenging situations
55
influences on prenatal development: stress and the mother (3)
1. the body secretes hormones that reduce the flow of oxygen to the fetus
2. the immune system is weakened (ilness in the mother can damage the fetal development)
3. the mother is more likely to smoke or drink and not excercese
56
influences on prenatal development: age of the mother: teens
there is an increased risk of:
- poor nutrition and lack of natal care
- incmplete maternal education
- poverty
- marital/relationship difficulties for mom
57
influences on prenatal development: teratogen
this is an agent that causes abnormal prenatal development
- there are 3 major catagories
- drugs
- diseases
- environmental hazards
58
influences on prenatal development: drugs: thalidomide
a drug used to treat morning sickness in the 1950's caused babies to develop serious abnormalities, sometimes including missing limbs
59
influences on prenatal development: drugs: asprin
particularly with heavy use, linked with deficits in intelligence, attention and motor skills
60
influences on prenatal development: drugs: caffine
with heavy use it can lower the birth weight, and decrease muscle tone
61
influences on prenatal development: drugs: cocaine and heroine
delayed growth, irritablilty in newborns
62
influences on prenatal development: drugs: weed
lower birth weight, less motor control
63
influences on prenatal development: drugs: nicotine
delayed growth, possible cognitive impairments
- it constricts the blood vessels, reducing the oxygen and nutrients that can reach the fetus
- even second-hand smoke is related to reduced birth weight
64
influences on prenatal development: drugs: alcohol
fetal alcohol syndrome, cognitive deficits, heart damage, delayed growth
65
influences on prenatal development: drugs: alcohol: fetal alcohol syndrome
when a mom drinks too much when pregnant
| -problems with growth and cognition, and facial anomalies (down syndrome?)
66
influences on prenatal development: drugs: alcohol: fetal alcohol spectrum disorder (FASD)
group of conditions that include FAS
67
influences on prenatal development: diseases
most maternal diseases dont really affect the fetus, but some do
68
influences on prenatal development: diseases: aids
frequent infections, newrological dissorders, death
69
influences on prenatal development: diseases: chlamydia
premature birth, low birth weight, eye inflamation
70
influences on prenatal development: diseases: chicken pox
spontaneous abortion, developmental and intellectual delays
71
influences on prenatal development: diseases: cytomegalovirus
deafness, blindness, abnormally small head, intellectual delay
72
influences on prenatal development: diseases: genital herpes
encephalitis, enlarged spleen, improper blood clotting
73
influences on prenatal development: diseases: rubella (german measles)
intellectual delay, damage to eyes, ears and heart
74
influences on prenatal development: diseases: syphilis
damage to the CNS, teeth and bones
75
influences on prenatal development: diseases: toxoplasmosis
damage to the eye and the brain: learning dissabilities
76
influences on prenatal development: environmental hazards: lead
intellectual impairment
77
influences on prenatal development: environmental hazards: mercury
physical and intellectual developmental delay, cerebral palsy
78
influences on prenatal development: environmental hazards: PCBs
impaired memory and verbal skill
79
influences on prenatal development: environmental hazards: x-ray's
physical and intellectual developmental delay, leukemia
80
how do terogens influence prenatal development
1. the impact of the teratogen depends on the genotype of the organism
2. the impact of teratogens changes over the course of prenatal development
3. each teratogen affects a specific aspect of prenatal development
4. the impact of teratogens is not always evident at birth but may appear later in life
81
genetic counselling
this is used before conception
| -it invoves having an expert asses familial risk for various genetic dissorders
82
prenatal assessment: ultrasound
prenatal diagnostic technique that bounces sound waves off the fetus to generate an image of the fetus
- can be used by about 4-5 weeks after conception
- determines fetal position, presence of multiple fetuses, obvious physical deformities
- by 16-20weeks it determines the sex
83
prenatal assessment: amniocentesis
prenatal diagnostic technique that involves withdrawing a sample of anmniotic fluid through the abdomen using a syringe
- results in 2 weeks
- 1% risk of miscarriage
84
prenatal assessment: chorionic villus sampling (CVS)
prenatal diagnostic technique that involves taking a sample of tissue from the chorion
- can be performed 9-12 weeks after conception
- results in 7-10 days
- 2% rist of miscairrage
85
fetal medicine:
this is a field of medicine concerned with treating prenatal problems before birth
-medication or hormones can be injected into the amniotic cavity, into the mother, or into the umbilical cord
86
stages of labour: stage 1
12-24 hr for the first birth
| -the uterus begins progressively stronger conractions, cervix dialates to about 10cm
87
stages of labour: stage 2
about 1h
- baby passes through the cervix and vagina with help from the mother contracting muscles in her abdomen
- crowning happens (when you see the top of the baby's head)
88
stages of labour: stage 3
a few minutes
| -the mother pushes a few more times to expel placenta or afterbirth
89
preparing for childbirth: education
parents attend classes to learn basic facts about pregnancy and childbirth
90
preparing for childbirth: natural pain relief
- some people chose this because medication can decrease the mother's ability to push and can cross the placenta
- some methods include relaxation
91
preparing for childbirth: where to have the baby
- there has been a bit of a shift to home births
- a well trained person (midwife) is essential to a safe birth
- easy access to a medical facility is important, in case of problems
92
adjusting to parenthood:
-the mother experiences changes in physical size and hormone levels
-both parents must change routine
-there are many responsibilities that must be adopted
-
93
postpartum depression:
- this occurs in about 10-15% of new mothers
- this is depression suffered after childbirth, usually from the combination of hormonal changes, the adjustment to motherhood, and fatigue
94
postpartum depression: symptoms
- irritability
- feelings of low self-worth
- disturbed sleep
- poor appetite
- apathy
95
postpartum depression: contributors
- lots of hormones during the end of the pregnancy
- depression b4 pregnancy
- other life stress
- unplanned pregnancy
- lack of support
96
postpartum depression: dangers
- lack of warm mothering
- less touching the baby
- less effectiveness in feeding and sleep routines for the baby
- if it is long term there is a risk of insecure attachment and later antisocial behaviour in the child
97
birth complications:
many healthy women do not have any
| -if the woman is unhealthy there is an increased risk
98
birth complications: hypoxia
when the umbilical blood flow is disrupted and the infant doesnt get enough oxygen
- can lead to intellectual impairment or death
- if there is a sudden change in the heart rate of the fetus it can indicate lack of oxygen
99
birth complications: caesarean section (c-section)
when the baby is surgically removed (through an incision in the abdomen)
- necessary if the fetus is in distress, is in an irregular position, or has a head that is just to big for that tiny vagina
100
birth complications: preterm (premature)
babies that are born before the 36th week after conception
- often lag behind full-term infants in development for the first year
- if they are in a good environment they will catch up by about 2-3
101
birth complications: varyingly low birth weights
low: less than 5lbs
very low: less than 3 lbs
extremely low: less than 2 lbs
102
birth complications: low birth weight reasons and outcomes
reason: the risk is inreased with women that smoke, drink, or arent nourished properly
outcomes:
-for very low/extremely low: many do not survive, those that do lag in intellegtual and motor skills
-for low: they usually survive and the outcome depends on the environment
103
infant mortality
this is the number of nfants out of 1000 births that die before 1yr
-in canada it is about 5
